Exhaust silencer



June 6, 1944. o. JfRAlNVlLLE EXHAUST SILENCER Filed Feb. 17, 1943 2 SheetsSheet l R June 1944. o. J. RAINVILLE EXHAUST SILENCER Filed Feb. 17, 1943 2 Sheets-Sheet 2 QMW axffiaiizifz'lze Patented June 6, 1944 UNITED STATES PATENT oer-"ice nxnaos'r snnscnn Omer J. Bainville, South mam. Mass. Application February 11, 194:, Serial No. 476,220

4 Claims. (or m-ss) This invention relates to certain new and useful improvements in exhaust silencers and of the type generally employed with internal combustion engines for silencing or muiliing the discharge of products of combustion from such engines.

The primary object of the invention is to provide an exhaust silencer especially designed for use in connection with internal combustion engines and in which the explosive force of the exhausting products of combustion is dissipated or broken down into a multiplicity of relatively smaller blasts for the purpose of quieting the exhaust discharge and removing back pressure on the engine.

A further object of the invention is to provide an exhaust silencer of the foregoing character wherein the housing of the silencer has an exhaust pipe section from the engine entering the same, with said pipe section provided with a plurality of openings of gradually increasing sizes from the inlet end thereof toward the outlet with such openings arranged in circular series and with the series staggered for the lessening of noise incident to the flow of products of combustion therethrough and for eliminating back pressure on the engine.

with the above and other objects in view that will become apparent as the nature of the invention is better understood, the same consists in the novel form, combination and arrangement of parts hereinafter more fully described, shown in the accompanying drawings and claimed.

In the accompanying drawings:

Figure 1 is a longitudinal sectional view of an exhaust silencer for internal combustion engines, the center exhaust pipe within the outer casing being illustrated in elevation and showing openings therein of gradually increasing sizes toward the discharge end,

Figures 2, 3 and 4 are cross-sectional views taken on lines 2-2, 3-3 and 4-4 of Figure 1, showing the flutes gradually struck greater distances inwardly to provide increased resistance to the flow of products of combustion and increased sizes of lateral discharge openings,

Figure 5 is a cross sectional view taken on line 5-8 of Figure 1, showing the laterally apertured partition wall in the casing to which the adjacent end of the center exhaust pipe is connected,

Figure 6 is a cross-sectional view taken on line H of Figure 1, showing the second partition wall with lateral discharge openings therein offset 90' with respect to the partition wall shown in Figure 5,

Figure 'l is a detail sectional'viewtaken on line 1-1 of Figure 1. and

Figure 8 is a fragmentary longitudinal sectional view of the center exhaust pipe, the axial line thereof being indicated by dot and dash lines and showing the flutes increasingly bent toward said axial line in a direction toward the discharge end of the exhaust pipe.

Referring more in detail to the accompanying drawings, the exhaust silencer comprises a casing ll preferably of cylindrical formation and having closed front and rear end walls I l and I2 respectively, the front end wall H being provided with a center opening surrounded by a bearing collar I: for the support of an exhaust pipe ll while the rear end wall ll of the casing has a central opening therein surrounded by bearing collar ii for the mounting of an outlet pipe Ii exhausting to atmosphere.

The exhaust pipe It extends into the casing ID the desired distance which may approximate substantially two-thirds the length of thecasing and finds support at its rear end on a partition wall I] extending transversely of the casing I O and having a marginal flange anchored as at it to the wall of the casing. The connection between the rear end of the exhaust pipe H and partition wall I] is shown more clearly in Figures 1, 5 and 7 as comprising a base disk I! having an annular flange 2| received in the adjacent end of the exhaust pipe II and secured thereto as at 2| by rivets or like fastening elements, the base disk I! being anchored to the partition wall I! by means of rivets 22 or the like. As shown in Figures 1 and 5, the partition wall I] has a pair of openings 23 respectively positioned laterally of the exhaust pipe ll. A second partition 2| extends transversely ofthe casing l0 substantially midway between the cross partition I! and the rear end wall I2, said partition 24 having a marginal flange that is anchored as at 25 to the easing II and is further provided with a pair of transversely alined openings 26 respectively at opposite sides of the longitudinal axis of the casing and at a turn from the openings 23 in the partition II, the relationshipof the openings 23 and 26 in the partitions I1 and 2| being illustrated in Figures 5 and 6.

The exhaust pipe I! is provided with circular series of openings throughout its length within the casing and said openings are arranged in groups with the openings of each group succes sively increasing in size toward the partition wall l1 and in the production of these openings. l gs. ears or flutes are struck inwardly oi the exhaust flutes 28 and upon an inspection of Figures 2 to 4 and 8 it will be observed that the openings 21 increase in size in a direction toward the partition wall l1 and that the flutes 28 are of correspondingly increased lengths, Figure 2 showing the smaller openings and shorter flutes, Figure 3 showing larger flutes approaching the longitudinal axis of the exhaust pipe, while Figure 4 shows the flutes 28 contacting at their 'apices at the longitudinal axis of the exhaust pipe.

It will be understood that least impediment is ofiered to the new of exhaust products of combustion through the exhaust pip ll at the point of entry of the products into the pipe, the smaller vopenings 21 permitting the lateral escape of some gases into the casing I0, while impediment of flow is gradually increased as will be understood from an inspection of Figures 3 and 4 of the drawings, by the increased areas of the flutes 28. The gradual increase in size of the openings 21 and the resistance ofiered by the inwardly struck flutes that increase in area tends to deaden the noise incident to an exhaust and to relieve back pressure on the engine. The exhaust gases outletting through the openings 21 into the chamber 29 of the casing follow the direction of "flow indicated by the arrow lines and pass through the openings 23 in the partition l1 and then through the openings 26 in the partition 24 for outletting through the pipe ii to atmos- Dhere.

From the above detailed description of th invention it is believed that the construction and operation thereof will at once be apparent and while there is herein shown and described the preferred embodiment of the invention, it is nevertheless to be understood that minor changes may be made therein without departing from the spirit and scope or the invention as claimed.

I claim:

1. In an exhaust silencer of the character de- 1 scribed, a casing, an exhaust pipe entering one end of the casing and terminating in spaced relation to the other end of the casing, a cross partition in the casing-closing the inner end of the exhaust pipe and having openings therein laterally of the pipe, and said pipe having openings gradually increasing in' size in a direction toward said partition, and said openings being formed by inwardly struck flutes with the flutes partition.

gradually increasing in length and approaching the longitudinal axis of the exhaust pipe in a direction toward said partition."

2. In an exhaust silencer oi the character described, a casing, an exhaust pipe entering one end of the casing and terminating in spaced relation to the other end of the casing, a cross partition in the casing closing the inner end of the exhaust pipe and having openings therein laterally of the pipe, and said pipe having openings gradually increasing in size in a direction toward said partition, and a second partition in the casing between the first-named partition and the outlet end of the casing and having openings therein out of line with the openings in the firstnamed openings in the first-named partition,

and said openings being formed by inwardly struck flutes with the flutes gradually increasing in length and approaching the longitudinal axis of the exhaust pipe in a direction toward said 3. In an exhaust silencer of the character described, a casing, an exhaust pipe entering one end of the casing and terminating in spaced relation to the other end of the casing, a cross partition in the casing closing the inner end of the exhaust pipe and having openings therein laterally of the pipe, and said pipe having openings gradually increasing in size in a direction toward said partition, and said openings bein formed by inwardly struck flutes with the flutes gradually increasing in length and approaching the longitudinal axis of the exhaust pipe in a direction toward said partition, the flutes adjacent the partition contacting on the axi line for directing the products of combustion through said openings.

4. In an exhaust silencer of the character decribed, a casing, an exhaust pipe entering one end of the casing and terminating in spaced I relation to the other end oi the casing, a cross partitionv in the casing closing the inner end of the exhaust pipe and having openings therein laterally of the pipe, and said pipe having openings gradually increasing in size in a direction toward said partition, and a second partition in the casing between the first-named partition and the outlet end of the casing and having openings therein out of line with the openings in the firstnamed openings in the first-named partition, and said openings being formed by inwardly struck flutes with the flutes gradually increasing in length and approaching the longitudinal axi of the exhaust pipe in a direction toward said partition, the flutes adjacent the partition contacting on the axis line for directing theproducts of 

